Discovery 4 Restricted Gearbox Mode

[Dealc]

Hi Folks,

I have a 2012 D4 and have now taken it offroad twice. Neither time has been through difficult terrain and I have selected gravel and grass as the 4WD type. On both occassions I used HDC to demonstrate it to my sone, however the hills were not that big and it was not actually required.

Here is the problem.

Each time I have been offroad the gearbox has gone into restricted mode after about half an hour in 4WD. No rhyme and no reason.

A restart clears the error but until then it stays in the designated 4th gear and you can change nothing.

Landrover came up with the fantastic solution (or so the Dealer says) of changing the transmission fluid to resolve the issue. It took three months to get new fluid in and then the 2nd off road adventure, same thing.

I really want to take this car offroad for real but am very hesitant to do so due to this issue.

Has anyone else experienced it and if so how do I solve it?

Yes it is still under warranty but it feels like the Dealer is providing lip service only and an email to LR Australia has not yet received a response.

Any help anyone can offer would be appreciated.

[Graeme]

If you're travelling slowly in high range then the gbox oil could be overheating from torque converter slippage, in which case use low range.

[BobD]

I'm not sure what you mean by having the car in 4WD since it is always in 4WD. However, I agree with Graeme about the overheating transmission if you are not using low range. The D4's systems all adapt to off road driving when it is in low range so the car is designed to be used in low range in slow off road conditions.


I once used high range on a beach in Esperance to try to keep up with my son in law who was flogging along at about 80 in his 80 series. After a while the car just started losing power until we got really slow and had to stop and then got bogged! I think the transmission was over heating so it cut engine power to reduce the heat. Put it in low range rock crawl, got out of the bog and then drove the rest of the way at a proper speed (below 60) in low range sand mode, with no further problems.


I always use low range off road and have never had a problem, except that one time when I used high range and pushed the car too hard in difficult conditions.


Bob

[Meken]

LR experience "driver" told me not to bother selecting special programme in the hill work in the D4 at the weekend. Apparently the D4 works it all out for itself (car leaning downhill will make it engage cdl ! ) I did use Hdc and it worked a treat! Maybe grass gravel setting is making the tranny work too hard in the conditions because it's trying to avoid wheelspin. Did the dealer report any faults from the bcu or the tcu ?

[BobD]

LR experience "driver" told me not to bother selecting special programme in the hill work in the D4 at the weekend. Apparently the D4 works it all out for itself (car leaning downhill will make it engage cdl ! ) I did use Hdc and it worked a treat! Maybe grass gravel setting is making the tranny work too hard in the conditions because it's trying to avoid wheelspin. Did the dealer report any faults from the bcu or the tcu ?



The best way to get an understanding of what the various off road modes do, other than purchasing Gordon's (GOE) invaluable book, is to look at the FAQ. I don't think that the "driver" gave you a very good understanding of what is actually happening, from your comments.


Bob

[Meken]

Thanks Bob, he did explain quite well the modes (and I did know the principles but not exactly what the car is doing mechanically - locking diffs etc).
I think more the point he was making was the rocky loose-ish tracks we were climbing/ descending did not require any special tr mode selected (would have only been mud/ruts or rock crawl anyway) and the car was doing it on the fly anyway as we had the display on and could see the cdl or the rear diff locking unlocking as we drove along. - just my 2 bobs worth

[scarry]

The latest RRS has the auto setting for the TR so it sorts it out itself.
The D4 doesn't,i would use the mode that is needed.

[Meken]

Sure I don't disagree - especially sand, but we did do all of the circuit in normal mode in low range and it wasn't going to be stopped

[BobD]

The D4 will work OK in standard setting but it will work so much easier and better in the correct setting for the terrain, especially in low range. It is still a 4WD with traction control and locking centre diff to suit the traction demands, even in the standard terrain setting or on road.


The main thing is to get out there and try it all out and enjoy the capabilities of the machine.


Bob

[jammers]

I had this similarly recently. My trigger was on a down hill coast - it would through a gearbox fault. Mechanic suggested that the egr was sticking causing a weird message to the gearbox. Some intake cleaner and so far so good.

D4 My10 2.7 ~110k km.

[Celtoid]

I'm not sure what you mean by having the car in 4WD since it is always in 4WD. However, I agree with Graeme about the overheating transmission if you are not using low range. The D4's systems all adapt to off road driving when it is in low range so the car is designed to be used in low range in slow off road conditions.


I once used high range on a beach in Esperance to try to keep up with my son in law who was flogging along at about 80 in his 80 series. After a while the car just started losing power until we got really slow and had to stop and then got bogged! I think the transmission was over heating so it cut engine power to reduce the heat. Put it in low range rock crawl, got out of the bog and then drove the rest of the way at a proper speed (below 60) in low range sand mode, with no further problems.


I always use low range off road and have never had a problem, except that one time when I used high range and pushed the car too hard in difficult conditions.


Bob


Hi Bob,


I'm on D4 #2 ... which hasn't been tested off-road yet (only 7K on the clock) but I can't wait to try it. I'm assuming it will be as good if not better than the 2009 MY10 that it replaced.


I've driven on Fraser Is, Moreton Is and Bribie Is through wet and dry sand of varying thicknesses at lots of different speeds, based on the conditions (both low and high range) and have never experienced what you have described. These islands have a very high silica content in their sand and it becomes like talc when really hot and dry. Conversely it gets very heavy and deep when wet.


I've stood outside my D4 after some of the harder driving and you can smell the transmission.....the heat off it. But never once did it do what you experienced.


I've driven on all the varying surfaces at speeds close to 100kph and down to 5, in both low and high range ... never an issue.


If you were to get a repeat of the scenario, I'd be asking LR why. As it just isn't right.


Then again ... how fast were you actually doing LOL?


Cheers,


Kev.

[BobD]

The 80 was driving in the wave zone on hard sand and through the salt water, hence he could do greater than 80. I was doing about 80 in soft sand on road tyre pressures well away from the water, so the car was working extremely hard, full power. I have never experienced anything similar before or since but I could only put it down to the car protecting itself from me.


My car is an early 2010 3l SE and has now done 160,000km and is in for its major service. I do heaps of soft sand driving in WA but I always use low range and stick to about 60 max in most conditions. I only did that high speed run in high range to try to keep up without immersing the car in salt water, something I don't usually do. I also usually run on 18psi, not 40, so that was pretty stupid too. Once we lowered the tyre pressures and used low range we didn't have any further problems.


The funny thing is the 80 got stuck at the end of the run in a creek flowing out to sea when he tried to climb the 1m high vertical bank and the flowing water sucked the back down into the sand. I broke an 11000kg snatch strap (and nearly went through the windscreen) trying to get him out but despite much digging and snatching with up to three cars at once he was stuck there all night while the tide rose to the top of the back seat. He ended up getting pulled out by a farmer in his heavy machinery the next day and drove home in front wheel drive when something jammed and the rear tail shaft broke.


The 80 is still going over a year later and surprisingly doesn't show any evidence of the dunking. However, he spent days removing everything and cleaning everything to try to stop it rusting.


Bob

[Celtoid]

The 80 was driving in the wave zone on hard sand and through the salt water, hence he could do greater than 80. I was doing about 80 in soft sand on road tyre pressures well away from the water, so the car was working extremely hard, full power. I have never experienced anything similar before or since but I could only put it down to the car protecting itself from me.


My car is an early 2010 3l SE and has now done 160,000km and is in for its major service. I do heaps of soft sand driving in WA but I always use low range and stick to about 60 max in most conditions. I only did that high speed run in high range to try to keep up without immersing the car in salt water, something I don't usually do.


The funny thing is the 80 got stuck at the end of the run in a creek flowing out to sea when he tried to climb the 1m high vertical bank and the flowing water sucked the back down into the sand. I broke an 11000kg snatch strap (and nearly went through the windscreen) trying to get him out but despite much digging and snatching with up to three cars at once he was stuck there all night while the tide rose to the top of the back seat. He ended up getting pulled out by a farmer in his heavy machinery the next day and drove home in front wheel drive when something jammed and the rear tail shaft broke.


The 80 is still going over a year later and surprisingly doesn't show any evidence of the dunking. However, he spent days removing everything and cleaning everything to try to stop it rusting.


Bob


I had a little 'incident' on Fraser when the car was quite new and I was quite new to the car. I was avoiding the wave zone as well .... many good reasons for that including your point about not wanting a salt bath, but unfortunately came across an infamous Fraser Island wash-out at about 60kph....."ladies and gentlemen please brace for landing"!!! I'd hate to do the math on the actual energy the car absorbed and yet the only damage was limited to the wheels. Still completely drivable but not quite true after that. Incredibly tough car. Wheels fixed ... a few months later when the slight vibration kept annoying me ... and then good as gold!


I have no idea why you had that loss of power but I doubt it was the conditions or your driving ..... just one of the LR's little quirks.


We bag Toyotas ... but they aren't that bad, just not as good as a D4 :-). I did laugh recently at a mate who bought an LC 200 based on the issues I'd had with my first D4 .... which turned out to be a loose earth lead. He still looks at my D4 longingly ... I see his sideways glance ;-) Poor bugger!